Fuse mechanism for explosive shells



June 12, 1928.

R. L. BARTLETT FUSE MECHANISM FOR EXPLOSI'YE 'SHELLS 2 `Sheets--Sheet l Filed Feb. 10. 1926 vwantoz M QM@ G atented .lune l2, 192e RAYMOND L. BARTLETT, F BROOKLYN, NEW YORK, ASSIGNOR 0F THREE-FOURTHS TO i SIDNEY MABANOV, 0F NEW YORK, N. Y. I

FUSE MECHANISM FOR EXPLOSIVE SHELLS.

itpplieaatien ed February This invention relates to munitions of war and has particular reference to fuse ignited explosive shells.

Among the-objects of the invention is to provide an explosive equipped` with fuse and firing mechanisms so constructed as to render the apparatus safe against premature firing or explosion, enabling the device to be handled and transported with impunity lunder l0 all circumstances so long as the actuator mechanism intended for the firing of the fuse is not caused to be operated.

A. further object of the invention is to provide safety fuse mechanism for explosive l5 shells constructed of a minimum number of parts and yet, possessed of ample facilities for such control or regulation of the firing of the devices as will make it. suitable and eective for its purpose and without de- 2@ tracting from its characteristics of safety.

With the foregoing and other object-s in View the invention consists in the combination and arrangement of parts hereinafter described and claimed, and while the invention is not restricted to the exact details of construction disclosed or suggested herein, still for the purpose of illustrating a prac-L tical embodiment thereof reference is ha to the accompanying drawings in which like reference characters designate the same parts in the several views, and in which- Figure 1 is a front elevation of an explo` sive shell embodying my improvements, -a portion of the leading end thereof being 1n section.`

Fig. 2 is an enlarged vertical section of the principal parts constituting and associated with, the fuse mechanism.

Fig. 3 is a view somewhat similar to Fig. 2, the view being as from the right of Fig. 2, but with the relatively lmovable parts in the same relative positions as shown in Fig. 2.'v

Fig. 4 is a view in a general way similar to Fig. 2, the body and fixed portions of the shell being` in the same position as in Fig. 2, but with the relatively'movable parts in changed or armed position.

Fig. 5 is a view similar to Fig. 4, but with the sectiontaken as viewed from the right of Fig. 4.

Figs. 6 and 7 are vertical sectional views showing details of the firing pin or plunger and the parts co-operating therewith or holding it in safety position.

10, 192. Serial No. 87,289.

Fig. 8 is a horizontal sectional detail about on the line 8 8 of Fig.- 3.

Fig. 9 is a horizontal sectional detail about on the line 9--9 of Fig. 2.

Referring now more specifically to the drawings 1 show at 10 a hollow shell of any suitable material, design, or construct-ion, but having an explosive chamber l1l thereinv normally closed by a heavy point or nose 12. The upper or trailing end of the shell 10 is provided with a threaded boss 13 and is further provided with a central hub 14 having a smooth cylindrical outer surface and providing in its upper central portion a seat 15 for the fulminate cap or primer. Leading downward and laterally from said seat 15 is a port 16.

Extending upwarc the shell 10 is a housing or cap 17, shown as of substantially conical formation. The lower end of the cap is screw threaded at- 18 upon the upper reduced end 19 of a coupling ring 20 whose lower end is threaded at 21 upon the boss 13, making a reliable connectionbetween the shell and `the cap- 17 and the parts housed within the cap.

22 indicates a sleeve of generally cylindrid cal form and fitted for limited rotation upon the hub 14, but this sleeve has a laterally project-ing base or flange portion 23 seated upon the boss 13 around the hub 14 and having a frusto-conical or beveled outer bearing periphery 24 overwhich projects a similarly formed inner surface of the coupler 20, whereby the sleeve 22 is held from movement endwise relatively to the shell 10 and cap 17. Any suitable means may be provided to lock the sleeve from relative rotation varoun'd`the hub 14, either befre or after the parts are caused to assume the armed position. To this end I provideftwo independent and vertically movable pins,- a latch pin 25 extending upward along the above the upper end of sieA sleeve 22 andpreferably located in a bore v formed in one side wall thereof. The lower end of this pin 25 is seated normally in a pit 26 formed in the boss 13, while the up-. per end of this pin is fitted-with a head27 whose upper surface is flat. This head is of arcuate form in plan, see Fig. 8, and one end thereof projects farther than the other from the pin 25, the projected endsbeing beveled off beneath as shown at 28. Again, the sleeve 22 is bored upward from its base as shown at 29, this bore being spaced circumferentially 90 from the pin 25 and at the same distance radially from t-he center of the sleeve vand hub 14. In this bore y29 is fitted a lock pin 30 riding normally upon the fiat upper surface of the boss 13 and against the .expansive force of a spring 31 located between the pinl and the closed end of the.

bore 29. This lock pin 30 therefore is adapted to drop or snap under the force of the spring 31 into the pit 26 when the sleeve 1s rotated through"`90 or from the position of Fig. 3 to that of Fig. 4. Furthermore, the base portion of the sleeve v22 is provided with an outwardly and downwardly inclined port 32 having normally no communication with any other port or opening asin Fig. 3, b ut adapted when the device is armed as in Fig. 4, to register with the port 16 atene end and with the port 33 at the other end, said port 33 communicating with the explosive chamber 11. Formed in the upper surface portion of the boss 13 is a circular or arc shaped channel 34 preferably concentric with the entire construction, and located in this channel is a contractile coil spring 35, one end of which is anchored at 36 to the shell structure, while the opposite end is anchoredv to a pin or hook 37 extending into said channel from the lower or base portion 23 of the sleeve 22. In the normal safety position of the parts the sprin is under tension and is so held by virtue o the latch rpin 25, but when the -latch pin is lifted from'the pit 26, the spring causes the sleeve 22y to rotate sharply through 90 until the lock pin 30 snaps into the pit 26, the parts being then in the position shown in Fig. 4, with ported communication from the fulminate seat to the interior of the chamber 11.

A series of stabilizing blades 38 are secured to and carried by the upper portion of the shell construction and"extend 1n parallel relation to one another upward for thel purpose of insuring that the nose 12 will always be forward -or downward when the device is delivered from a high elevatqion vsuch as an aeroplane or other carrier. Mounted centrally of the device and the trailing ends of the stabilizer blades is an actuator in the nature of a rotary propeller 39 connected to a shaft 40 journaled for free rapid rotation around the general axis of the device. 41' is a spindle arranged coaxially of the shaft 40 and withwhich said shaft has detachable connection through a pin 42 and bayonet slot connection at 43 with a coupling sleeve 44, the sleeve beingv 4keyed .at 45 to said spindle. slot is so disposed that it has an open end projected upward or toward the actuator propeller, while the closed or blind end thereof in which 'the pin 42, is normally seated is directed laterally in a direction reverse vtothe direction in which the actuator is normally rotated. When the actuator Said bayonet shaft 40 is inserted into the socket end of 't the coupling sleeve it bears against and compresses an expansion coil spring 46, by virtue of which the pin is normally held in its seated position at the blind end of the slot. The spindle 41 is journaled for free rotation in a bearing 48 having internally threaded connection with the upper end of the sleeve 22 and so held in position fixed to said sleeve, the s indle being anti-frictionally mounted )re erably by upper and lower racels of antiriet-ion balls 49 and 50 respective y.

The lower end ofthe .spindle 41 is provided with a cylindrical head 51 having a diametrically arranged tongue 52 extending across its lower end in which is formed a transverse hole 53, and above the tongue the head is drilled with a radial hole 54 in which is slidably fitted a pin 55,r such pin being held normallyhoused 'entirely within the hole 54 by means of a collar 56 or` retaining thimble surrounding and fixed to the body portion of the plunger or firing pin 57. The firing pin is transversely bored at 58 to register with the hole l53 in normal position as in Figs. 6 and 7, and fitted in said registering holes are a pair of studs 59 urged normally toward veach other and in contact with each other within the hole 53 by means of light springs 60... The remote ends of the springs are in abutment relation with the inner surface of the thimble 56. When t-he device is dropped or Areleased from its elevated position the vnose 12 drops in advance of the actuator end thereof, and the medium through which the projectile or bomb passes causes the actuator propeller to spin rapidly with its connected shaft 40 and' thimble 41, thereby causing the firing pin or plunger 57 to rotate rapidly. After asutlicient drop to enable the medium to speed up sulliciently the rota` tion of the actuator and connected parts, the

studs 59 will be thrown away'by centrifugal force from each other against t-he force of the springs 60, thereby clearing the hole 53 and the tongue 52, at which time the firing in 57 and connected thimble 56 will drop low and free from the spindle head 51 l and its tongue as shown in Fig. 5. The head 5,1, however, continues its rotation, with the pin 55 maintained in the same plane, which pin then slides outward radially by centrifugal force and takes under the beveled or cam end 28 of the latch pin head 27. The' vspindle and its head 51 being maintained in the same endwise position relatively by virtue of the bearings 49 and 50, the engagement of lsaid lifting pin 55 with the latch head will cause the latch to be lifted free :from its pit'26. Thereby the sleeve 22 is unlocked, setting the spring 35 free to rotate the sleeve into the position of Fig. 4 where it will vbe limited in its rotation by the locking action of the lock pin 30. This lock pin the consequent explosion of the charge in the is positive in its action and serves .to hold the parts in the position shown in Fig. 4 with the ports 16, 32, and 33 in communication with one anot-her. The action of this pin furthermore serves to stop suddenly the rotation of the sleeve 22 and coupling sleeve 44. At this time, however, the actuator, spinning at high speed will-cause the pin 42 to leave its normal position as shown in Fig. 2, follo-Wing along the slot 43 to the position of Fig. 4 and thence on until it reaches the vertical open end portion of the slot, when the spring 46 will throw the actuator upward relatively clear and free from the device, thereby reducing still further the retarding effect of the medium through which the device is passing at the time. The parts will now be in the position of Fig. 5, the firing pin being in armed position and with the actuator detached. `When the device strikes against an obstacle, causing the stopping or retardation thereof, the firing pin 57 continuing in motion at the speed it has already acquired will cause the ignition of the fulminate cap at 15 and chamber l1. A light cushion spring 61 located between the firing pin 57 and the upper end of the hub 14 prevents premature contact and ignition of the fulminate, but 'the force of this spring is not sufficient to prevent the tiring when the device is stopped by impact against an obstacle.

Surrounding t-he. sleeve 22 and within the cap 17 is a chamber or` space with whichI the primer has normal communication through the port 16 and a safety vent 62 when in the unarmed position of the parts. The ports 62 and 32 are spaced c-ircumferentially from each other at 90, corresponding to the limited rotation of the sleeve 22 in practice. I wish to point out also that the latch pin 25 is held down normally in engagement with the pit 26 by virtue of a coilspring 63 seated in a hole 64 formed in the upper vportion of the sleeve 22 and in alignment with the pin 25. The lifting action, however, of the pin 55, as above explained, overcomes the force of this spring 63. It will be observed also thatsince the head 51 with its lifting pin partakes of the same high speed of rotation as the actuator, when the lifting pin acts upward upon the head 27` and releases the latch pin 25 from the pit 26, the lifting pin 55 impinges against said latchpin and so the momentum of the actuator causes a rotational im ulse to be given to the safety sleeve 22 auxiliary to that of the spring 35, but the rotation of the sleeve 22 as well as that of the head 51 and spindle 41 isv positively and suddenly stopped by the" functioning/of4 the locking pin 430, andit is by this fact that the actuator is enabled to free itself at the point 42, 43 as above-set forth..

rom the nature of, this invention it is frequently desirable and sometimes essential that the body 10 with its charge ofhigh explosive be separated from the fuse mechanism, as for transportation or storage purposes. l wis to point out therefore that the constructionb as set forth herein is peculiarly adapted for such separation purposes. By simply unscrewing the coupling collar 20 from the body 10 all the parts above the body 10 may be removed bodily and directly therefrom without in any manner disturbing the relative positions of the parts as set forth in Fig. 1 During such uncoupling action the sleeve 22 is held from rotation by means of the latch pin 25 but it and the parts associated with it are movable upward and away from the boss 13. rlhe parts may be reconnected at any time by simply hooking the spring 35 upon-its respective connections, putting the parts back into original position.l

.I claim:

1. An explosive shell comprising a body having a chamber for the explosive, said body having a hub providing a primer seat, a sleeve fitted for limited rotation around said hub, -and means to hold the sleeve from rotation, said hub and body having aligned but spaced ports leading from the primer seat to the chamber, said sleeve having a port which in one position of the sleeve is spaced from the ports aforesaid Vbut which when the sleeve is rotated aligns therewith to effect communication between the primer and the chamber.

2. In an explosive shell, the combination of a shell body having a chamber for ex- 4. .Mechanism as set forth in claim 2 in-y lio cluding a locking member serving to limit y nthe movement of said member to such position as to insure the communication from the primer to the 'explosive chamber and to hold said member in such position.

5. Mechanism as' set forth in claim 2 in which the movable member is of hollow cylindrical form and movable around the axis of the shell, and provided with a spring for `moving it as aforesaid.

6. In explosive shell mechanism, the vcom- `bination of a main body having an exploxsive chamber, the body being provided with u'an externally threaded boss and a hubr ex- 'f the explosive chamber said shell having a tail portion, a coupling collar having engagement with said. tail portionv and said threaded boss and serving to hold the safety sleeve in positionA against the boss, and means actuatable as a result of movement of the device through a medium to control the position of the safety sleeve. 7. Mechanism as set forth in claim 6 in which the collar and safety ,sleeve are provided with complemental frusto-conical bearing surfaces.

8. In explosive shell mechanism, the combination of a main body having an explosive chamber therein and havinfr primer port connections through one end thereof, stabilizing means to compel the device to travel in 4a certain direction, la safety sleeve mounted for limited rotation around the axis of the shell at the ported end thereof, a coupling collar securedto the ported end of the shell body` and havin bearin connection with said sleeve serv' ggto ho d the same from endwise movement, locking pin means to control the rotationof the sleeve, and firing mechanism including a plunger, meansl to hold the plunger spaced from the primer, and means to release the plunger after the device has acquired a predetermined velocity. f

9. In explosive shell mechanism, the combination with a main shell having an explosive' chamber and having at one end a primer seat, and stabilizing means at the rear end of the shell'to compel the shell to move in a predetermined manner through a medium, of, firing mechanism for the primer including an actuator caused to be rotated as a ,result of the movement of the shell` through the medium, a plunger adjacentto but spaced normally from the primer, means l connecting the plunger to' the actuator for initial rotation therewith, said connecting means being releasable as the result of the acquirement of a predetermined speed of rotation, setting the plunger free to move toward the primer, and protecting means to -prevent premature explosion of the explosive irrespective lof the ignition of the primer.

10. In explosive shell mechanism, the combination with a main body having an explosive chamber and having a primer seat fromwhich leads a port toward the explosive chamber, and firing mechanism for the anism extending into said primer, of a safety member to establish communication between the primer andy the chamber during flight of the shell, and means to control the movement of the safety member, the safety member being a hollow cylinder provided with a pair of longitudinal bores and a pair of locking pins fitted slidably in said bores at equal distances radially from the axis of the cylinder, and the shell body being provided with a pit so disposed as to receive said pins in succession. A

11. In explosive shell mechanism, the combination of al main body having an explosive chamber and having a hub forming a primer seat and having a port leading from said se'at toward the chamber, a safety sleeve fitted for limited movement around said hub' and serving normally to obstruct communication from said port to the explosive chamber but having a vent leadin in a direction remote from the explosive chamber, said sleeve having another port adapted to 'establish communication between the primer port and the, explosive chamber after movement ofl the sleeve, a firing plunger within the sleeve, Vmeans normally holding the sleeve in safety position, and actuator mech.-

sleeve serving after a predetermined movement of the device to release the firing plungerand withdraw said locking means from holding position, setting free the sleeve for rotation to armed position.

' 12. Mechanism as set forth in claim 2 including an actuator so designed as to acquire a high speed of movementas av result of the movement of the shell, the momentum of the actuator serving to release the safety member.

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13. Mechanism as set `forth inclaim 2 in `be rotated through a limited degree as a result of they acquirement of a predetermined speed of movement of the shell, a fan to ro- 'j tate said member, and means to stop positively the rotation of said member, said stopping means serving to cause the disconnection between the fan and the' member.

14.` In mechanism of the character set forth, the combination of a body having' a chamber for a charge of explosive, and firing mechanism for the explosive including a rotatablel actuator, a firing means, and centrifugally operated means attaching the firing means to the actuator arid releasing said firing means when said actuator attains a predetermined speed of rotation.

',15. In an explosive shell, the combination of a shell body having a chamber for explosive and a primer therefor, means serving normally to cut off communication between the primer and the chamber, means to establish communication between the primmeans on release of the latter. by centrifugal force due to the rotation of er and the chamber when the shell attains plunger to the actuator for rotation there-I a predetermined speed of movement, and rewith, said attaching means including a radi- 10 silient means actuating said last mentioned ally r f Vable pin, said pin being actuated.

16. Explosive shell mechanism comprising the actuator and thereby releasing said a body having a chamber for a charge of plunger.`

explosive, a firing plunger, a rotatable actu- In testimony whereof I afiix my signature.-

atorfand means normally attachingy the RAYMOND L. BARTLETT. 

